Roller assembly with one-way braking means

ABSTRACT

AN INCLINED POWER-DRIVEN CONVEYOR OF THE TYPE HAVING A PLURALITY OF ROTATABLE, ARTICLE-TRANSPORTING ROLLERS POSITIONED ABOUT CHAIN-DRIVEN AXLES DISPOSED TRANSVERSELY OF THE CONVEYOR, WHEREIN A LONGITUDINALLY-OSCILLATABLE PAWL MEMBER AND A RATCHET MEMBER ARE ENCLOSED WITHIN THE RESPECTIVE ROLLERS FOR RESTRAINING DOWNWARDLY-DIRECTED ROTATION OF THE LOAD-BEARING SURFACES OF SAID ROLLERS, AND FOR ALLOWING UPWARDLY-DIRECTED FREE ROTATION OF SUCH ROLLER SURFACES.

ROLLER ASSEMBLY WITH ONE-WAY BRAKING MEANS Original Filed Jan. 5, 1968 C. A. HEYNE Sept. 21; 1971 4 Sheets-Sheet 1 INVENTOR. I

Sept. 21 1971 Original Filed Jan. 5, 1968 (3. A. HEYNE I ROLLER ASSEMBLY WITH ONE-WAY BRAKING MEANS -4- Sheets-Sheet 2 I N VENTOR.

' Sept. 21, 1971 Original Fild Jan. 5, 1968 c. A. HEYNE ROLLER ASSEMBLY WITH ONEWAY BRAKING MEANS 4 Sheets-Sheet 5 q 21, 1971 c. A. HEYNE' 3,606,938

I ROLLER ASSEMBLY WITH ONE-WAY BRAKING MEANS Original Filed Jan. 5, 1968 I 4 Sheets-Sheet 4- "aw/.4444, v

United States Patent Olhce 3,606,938 ROLLER ASSEMBLY WITH ONE-WAY BRAKING MEANS Clarence A. Heyne, Toledo, Ohio, assignor to Owens-Illinois, Inc.

Original application Jan. 5, 1968, Ser. No. 695,951, now Patent No. 3,503,490, dated Mar. 31, 1970. Divided and this application July 30, 1969, Ser. No. 870,855

Int. Cl. F16d 63/00 US. Cl. 18882.1 4 Claims ABSTRACT OF THE DISCLOSURE An inclined power-driven conveyor of the type having a plurality of rotatable, article transporting rollers positioned about chain-driven axles disposed transversely of the conveyor, wherein a longitudinally-oscillatable pawl member and a ratchet member are enclosed within the respective rollers for restraining downwardly-directed rotation of the load-bearing surfaces of said rollers, and for allowing upwardly-directed free rotation of such roller surfaces.

CROSS REFERENCES TO RELATED APPLICATIONS This is a division of my copending application filed Jan. 5, 1968 and now issued as U.S. Pat. No. 3,503,490.

BACKGROUND OF THE INVENTION This invention generally relates to article conveying devices; more particularly, it relates to power-driven roller conveyors which are adapted for article transportation and article accumulation,

In practice, the use of level accumulating conveyors is quite extensive. These conveyors typically include a series of rotatable rollers which are continually translated in a level linear path by means of a chain driving element attached to the roller shafts. Cartons, which are supported by adjacent rollers, are transported along the conveyor as a result of the rollers translational movement. Moreover, should some retaining force be applied to the transported cartons whereby these cartons would no longer be free to unitarily translate with their appurtenant supporting rollers, the chain, because of the rotatable nature of the rollers, can drag the rollers beneath the carton without any adverse cutting or scoring. Thus, a succession of cartons may be continually supplied to an accumulating zone by the translating rollers and being restrained in this zone the chain is free to slip beneath the accumulated cartons without marring their appearance.

Unfortunately, the foregoing :type conveyors are only operable when the cartons are to be transported and accumulated in a horizontal plane. Considering the fact that in most manufacturing operations there is a substantial employment of descending conveyors, it would be desirable to provide for a descending conveyor which possesses carton accumulating features.

SUMMARY OF THE INVENTION In accordance with this invention there is provided an inclined accumulating conveyor possessing features which allow controlled descent of cartons along the conveyor.

More particularly, in accordance with this invention,

3,606,938 Patented Sept. 21, 1971 there is provided an inclined conveyor of the type having a plurality of translating rotatable rollers wherein unidirectional roller arresting means are enclosed within the roller, the arresting means being operative to restrain downwardly-directed roller rotation but to allow upwardly-directed rotation. In the preferred embodiment, the unidirectional roller arresting means includes ratchet means carried by the respective rollers and pawl means adapted to interlock with said ratchet means in response to one mode of roller rotation, the pawl means undergoing a continuously slipping, longitudinal oscillation in response to the reverse mode of rotation.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and other advantageous features of this invention will become more apparent by reference to the drawings of which:

FIG. 1 is a longitudinal elevational view of a preferred form of conveyor of this invention;

FIG. 2 is a transverse elevational view of the conveyor of FIG. 1;

FIG. 3 is an enlarged vertical sectional view of an individual roller showing one operating mode of the roller arresting means of this invention;

FIG. 4 is a sectional view similar to FIG. 3 showing an alternate mode of operation;

FIG. 5 is a longitudinal sectional view of one roller taken along the line 55 of FIG. 3 and FIG. 6 is an exploded perspective view showing the pawl and ratchet members of one roller of this invention.

DESCRIPTION OF PREFERRED EMBODIMENT(S) Referring to FIGS. 1 and 2 there is shown a descending conveyor 10 for transporting and accumulating a series of cartons 12. Conveyor 10 includes a plurality of parallel carton-supporting rollers 14, each rotatably mounted by a bearing assembly (FIG. 5) disposed at each end of an individual shaft 18. In the preferred embodiment rollers 14 at least include an outer casing of a suitable material having a high coeflicient of friction; such as rubber for example. The rollers thereby provide a frictional contact with the respective cartons and, as will be subsequently seen, prevent uncontrolled carton descent along conveyor 10. The respective shafts 18 are affixed at each end to an inclined, continuous chain belt 20 and are movable in unison therewith. Thus, a pair of similar chain belts 20, as shown in FIGS. 1 and 2 support and transport the roller shafts 18. Suitable structural members 22 provide support for the inclined conveyor and include integral carton guide rails 24 and chain guide rails 26, the latter serving to define the angle of inclination of chain belt 20 and to provide tracking support therefor. Each chain belt 20 is supported at its raised extremity by an idler sprocket 28 and is driven and supported at its lower end by a similar sprocket 30. As shown in FIG. 2, a pair of drive sprockets 30 may be supported and driven in any suitable manner such as, for example, by positioning them on a transverse drive shaft 32 which is journaled in cross members 34 and rotated by a conventional motor-driven belt and pulley arrangement 36, and 38 respectively.

Referring now to FIGS. 36 inclusively, it will be seen that each of the rollers 14 and shafts 18 is provided with interacting devices which allow the load-bearing upper surfaces of the rollers to rotate freely in the upward direction of the conveyor (arrow A in FIG. 3) but restrain downwardly-directed roller rotation (arrow B in FIG. 4).

3 In the preferred embodiment, the interacting rotationcontrolling devices are enclosed within the rollers and include a ratchet member 40 and a pawl assembly 41 as shown in FIG. 5, the former generally being carried by the respective rollers 14 and the latter being appurtenant to the shafts 18.

Ratchet member 40 preferably comprises a tubular-like element unitarily and coaxially encased within roller 18 and being provided with a series of radially aligned, inwardly extending arcuate ledges or panels 44. The inner surface of the respective arcuate ledges define camming surfaces 46 and their respective edges define locking teeth 48. Preferably, three such ledges are provided, the respective ledges being in a circular array, and displaced by about 120 degrees. While the number of ledges may be modified, the most beneficial operation of the system will be accomplished by employing non-diametrically aligned ledges. This preferred relationship of the respective ledges will become more apparent subsequent to the description of the pawl assembly.

The pawl assembly includes a generally wing-shaped pawl 42 and a pawl supporting member 50, both of which are enclosed within roller 14 inwardly of bearing assembly 16. A locking collar 52 secured to shaft 18 is used to restrain the pawl assembly from slipping along the shaft. As shown in FIG. 6, pawl 42 includes opposed panels 54 and 56 respectively, which are linked by a downwardly convex, arcuate section 58. The longitudinal extremities of the respective panels are deformed to define invertedly-related cam-follower surfaces 60 and locking surfaces 62, i.e. panel 54 includes a downwardly and inwardly extending arcuate surface while panel 56 includes an upwardly and inwardly extending arcuate surface de fining the respective inverted cam-follower surfaces 60. PaWl support member 50 includes spaced flanges 64 which are stationarily mounted to shaft 18, the flange being joined by an annular section 66. For the purpose of supporting pawl 42, and to restrain any rotational movement thereof, annular section 66 is formed with opposed slots defining a lower set of supporting shoulders 68 and an upper set of shoulders 70, the latter engaging the upper surfaces of panels 54 and 56 to prevent rotation of pawl 42. It is important that the longitudinal dimension of pawl 42 exceed the diameter of annular section 66 thereby allowing the respective locking surfaces and cam-follower surfaces to project radially therefrom, and that pawl panels 54 and 56 be sufficiently long to allow limited longitudinal movement upon supporting shoulders 68.

In actual operation cartons 12 may be positioned upon rollers 14 and by means of the driven chain belt 20 are transported along the upper reach of the conveyor in a downward path. Since the tendency of the rollers, upon downward carton descent, will be to rotate in a counterclockwise direction due to the carton load thereupon (FIG. 4), the pawl and ratchet members are adapted to interact and restrain any such rotation. This is accomplished by the fact that upon initial counter-clockwise rotation locking teeth 48, which project inwardly of ratchet member 40, will engage the complimenting locking surfaces 62 of pawl 42. Since the upper shoulders 70 of support member 50 prevent the pawl from rotating in a counterclockwise direction as shown in FIG. 4, further rotational motion of the roller is prevented. Thus, controlled carton descent is obtained by regulating the traversing speed of chain belt 20.

Suitable means for restraining cartons 12 at the base of the inclined conveyor path is also provided. As shown in FIG. 1 a transversely disposed baflle 72 may be employed for this purpose. Thus, as the cartons are transported downwardly along conveyor 10, engagement with baffle 72 prevents further translation and the chain then drags successive rollers beneath the immobilized cartons. Here the ratchet and pawl members, 40 and 42 respectively, slippingly interact and allow upwardly directed roller rotation (FIG. 3) which precludes carton scoring and provides article accumulating features, the interaction being characterized by a substantially planar, longitudinal oscillation of pawl 42. Referring to FIG. 3 it Will be seen that upon upwardly-directed roller rotation, pawl camfollower surfaces 60 will ride upon ratchet camming surfaces 46 sequentially causing the pawl to be forced radially away from the respective camming surfaces. It is to facilitate this longitudinal oscillation of pawl 42 that, in the preferred embodiment, arcuate panels 44 are disposed in non-diametric relation.

From the foregoing, it should be readily apparent that cartons may be positioned upon the upper reach of the conveyor and, by regulating the speed of the motor-driven belt, they may be descended therealong in a selectively controlled manner. The possibility of run-away cartons is virtually eliminated because of counterclockwise rotational restraint exercised upon the respective rollers by the interlocking feature of the pawl and ratchet members. Thus, a tandem array of cartons, as shown in FIG. 1, may be moved from right to left until they are restrained by a suitable stop-member. Since the continual movement of the chain belt will cause the rollers to drag beneath, and in contact with, the lower surfaces of successively restrained cartons, these rollers should preferably be free to rotate in a clockwise direction if marring or scoring of the carton bottom surfaces is to be prevented. This feature is provided by the slipping interaction of the ratchet camming surfaces and the pawl cam-follower surfaces.

While the invention has been described with reference to the preferred embodiment, it will be appreciated that various modifications are possible. Accordingly, the foregoing is to be considered exemplary, rather than limiting and the true scope of this invention is as defined in the following claims.

I claim:

1. A roller assembly comprising a shaft, a roller having a relatively thin cylindrical wall and means connected to said wall rotatably mounting the roller on said shaft, cam means carried interiorly of said cylindrical wall and comprising plural radially inwardly directed curved cam surfaces peripherally spaced about said cylindrical wall in non-diametrically disposed relationship and a radial locking surface adjacent each cam surface, an elongated, wing-shaped cam follower member having opposed substantially planar end panels, a housing member removable and non-rotatably supported on said shaft, said housing including means supporting said cam follower member and permitting longitudinal shifting movement of said cam follower radially within said roller, the cam follower member having at each planar panel end a curved cam follower surface and a pawl surface, the said cam follower and pawl surfaces of one said panel end being inverted with respect to such surfaces of the other said panel end, the cam follower member being proportioned in length for limited movement transversely in said roller, either of the opposite said panel ends being alternatively engageable with one of said plural cam surfaces or one of said plural locking surfaces in response to the direction of rotation of said roller, whereby engagement of the cam follower and cam surfaces permits roller rotation in one direction or alternative engagement of one of said pawl surfaces with one of the said locking surfaces prevents roller rotation in the opposite direction.

2. The roller assembly of claim 1, wherein said cam means are formed from plural pierced areas of the said cylindrical wall each of which are bent radially inwardly of said roller cylinder at a radius shorter than said cylindrical radius and having a free inner end to form each of the respective curved cam and radial locking surfaces 3,606,938 *7. 6 sides of said shaft, said shoulders engaging said respective References Cited planar end panels and allowing limited longitudinal shift- UNITED STATES PATENTS mg movement of said wing-shaped follower member.

4. The roller assembly of claim 3, wherein said hous- 227,146 880 Campbell 18882.1X ing member further includes a second set of opposed 5 2,330,677 9/1943 Canfield 192*46 shoulders spaced from said first mentioned opposed 2,769,515 11/1956 Thomas et 193-35A shoulders and engageable with said planar end panels to restrain rotational movement of said pawl, the corre- GEORGE HALVOSA Pnmary Examiner sponding first and second shoulders defining parallel sur- U S Cl X R faces of a restraining slot on said housing for the Wing- 10 shaped member. 192-46; l9335A; 198l83; 242-l07.6 

